SyntaxTree: How to read full ValueText of a multi-line Raw Literal String (or: why is it different from a multi-line verbatim string?)

[BrunoJuchli]

Edit: It looks like I made a mistake in passing my "source code" to the parser. And I got confused .. so my bad ;-)

Question

How can I use a parsed SyntaxTree to get the whole value text of a multi-line raw literal string?
Why is it different from how we can retrieve the value text of a multi-line verbatim string?

How I Parse my Code

Using Microsoft.CodeAnalysis v4.8.0 (or 4.9.0-3.final), with:

CSharpSyntaxTree
    .ParseText(
       "source code - I'll give examples below",
       path: "dummy",
       options: CSharpParseOptions
           .Default
           .WithLanguageVersion(LanguageVersion.Latest));

Actual Behavior

Verbatim multi-line string

with the following source text:

S[@"a verbatim
    string text"];

Just to be sure that I don't make any mistakes, this is how I define it in my c# code:

@"
S[""""""a raw literal
     multiline string
     """"""];"

--> since i use a @-verbatim multiline string to declare the source, I need "" to escape a single ".

Result

ElementAccessExpressionSyntax.ArgumentList.Arguments contains a single ArgumentSyntax with an .Expression of type LiteralExpressionSyntax with .Token.ValueText = A verbatim\r\n string text.

=> I can get the string value via ((LiteralExpressionSyntax)argument.Expression).Token.ValueText.

Multiline Raw Literal String

S["""a raw literal 
       multiline string
       """];

Result

ElementAccessExpressionSyntax.ArgumentList.Arguments contains 4 ArgumentSyntaxs, where .Expression is:

• 0 - LiteralExpressionSyntax with .Token.ValueText = a raw literal`.
• 1 - IdentifierNameSyntax with Identifier.Text = multiline
• 2 - PredefinedTypeSyntax with .Keyword.ValueText = string
• 3 - LiteralExpressionSyntax with .Expression.Token.ValueText = ];`.

Note that ElementAccessExpressionSyntax.ToString() returns S["""a raw literal\r\n multiline string\r\n """];;

Question: how am I supposed to extract a raw literal multiline string from this?
Is this broken / buggy / support for multi-line raw literal strings is missing?

[BrunoJuchli]

Ok so it looks like I just got confused and didn't properly specify the multiline raw literal.

Here's how it works:

@"
S[""""""
     a raw literal
     multiline string
     """"""];"

resulting in a single argument with .Expression.Token.ValueText = a raw literal\r\nmultiline string.

[CyrusNajmabadi]

Your raw string literal is incorrect. It cannot cross multiple lines without starting with a new line after the initial quotes.

[BrunoJuchli]

Thanks, you're right, I got confused there :-/

[CyrusNajmabadi]

ElementAccessExpressionSyntax.ArgumentList.Arguments contains 4 ArgumentSyntaxs, where .Expression is:

Check the diagnostics on the syntax tree instance you get back. It should indicate the problem.